Effect Of 6 Months Of Supervised Resistance Training In Overweight Young Men

Abstract

The American College of Sports Medicine recommends resistance training (RT) as an integral part of an adult fitness program. RT should be of sufficient intensity to enhance muscular strength and endurance and to maintain or increase both fat-free mass (FFM) and physical function. One set of 8–10 exercises, 8–12 repetitions that condition the major muscle groups, 2–3 d/wk is recommended. However, other fitness experts have suggested that RT of at least 1 set to failure or multiple (3–6) sets are necessary to improve muscular fitness. While this strategy may potentially result in larger increases in muscular fitness than single set programs, adherence to this regime by untrained sedentary individuals is likely to be low, thus decreasing the programs long-term effectiveness. PURPOSE To determine the effect of a 6 month supervised RT program (1 set, 3–6 repetitions maximum (RM), 3 d.wk-1) on muscular strength (1 RM) and FFM (DEXA) in sedentary, overweight (mean ± SD) (BMI = 28.3 ± 2.3kgċm−2) young (age = 20.7 ± 2 yrs) men on a ad libitum diet. METHODS Nineteen men were randomly assigned to control (n = 8) or RT groups (n = 11). The exercise protocol consisted of 5 upper and 4 lower body exercises using weight machines. Controls maintained their sedentary lifestyle. One-RM for upper (chest press + lat pull) and lower (leg press) body and FFM were assessed at baseline, 3 and 6 months. RESULTS Adherence was 96 ± 2% with an average time to complete each exercise session of 15 ± 2 min. Upper body strength increased significantly (p <0.001) (31.3 ± 9.3%) from baseline to 3 months and from 3 to 6 months (17.9 ± 8.7%). Lower body strength also increased significantly from baseline to 3 months (17.8 ± 16.6%) and from 3 to 6 months (32.0 ± 33.7%). No changes in upper or lower body strength were noted in the control group. FFM was unchanged in both groups. CONCLUSION A single set RT program using 3–6 RM, 3 d.wk−1 resulted in continued increases in muscular strength and a very high adherence rate over a 6 month period in sedentary, overweight, young men independent of significant changes in FFM. This realistic training protocol may increase adherence and produce meaningful increases in muscular fitness as part of an adult fitness program. Supported by NIH Grant RO3 DK49181